Fabrication and characterization of starch beads formed by a dispersion-inverse gelation process for loading polyphenols with improved antioxidation

Macro-scale beads are ideal carriers for loading active ingredients, herbicides, and dyes due to their large storage capacity, porosity, and biodegradability. The aim of this study was to fabricate macro-scale beads using starch due to its low cost and biocompatibility. Pea starch beads and mung bean starch beads were first fabricated in soybean oil through a dispersion-inverse gelation process. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and fourier transform infrared (FTIR) spectroscopy were used to characterize the morphologies and behaviors of the beads. Results showed that the pea starch beads form a dense and uniform network when retrograded at 4 °C for 24 h with a pore size of approximately 300 nm. Furthermore, after retrogradation for 36 h, the pea and mung bean starch beads exhibited B-type structures and displayed maximum relative crystallinity of 21.2% and 19.4%, respectively. The starch beads have high loading efficiency for polyphenols and can enhance the antioxidant activity of polyphenols. Moreover, the polyphenols loaded into starch beads can release quickly in intestinal juice, indicating that the beads are expected to be a new carrier for loading and control release of water-soluble active substances or drugs.